Ergonomics is a fundamental part of product design, particularly for devices that are in physical contact with the user for long periods of time, such as, but not limited to, in-ear devices including earphones, hearing aids, and ear plugs. Comfort may be an important factor regarding a product's success. Product comfort may be achieved through a precise fitting of the device in the user's external auditory canal (EAC) and concha. However, it is well known that there is a large degree of morphological variation across individuals, particularly in the EAC, concha, pinna and pinna distance to the skull. Furthermore, there is a lack of comprehensive anthropometric studies available in the literature relevant to the design of products in this category.